In the medical field, it is common to use ultrasound diagnostic equipment to view internal organs of a subject. For example, in diagnosing prostate cancer, a diagnostician uses transrectal ultrasound (TRUS) to identify whether lesions are present as well as to determine the location, size and extent of lesions if present. Conventional ultrasound diagnostic equipment typically comprise an ultrasound probe for transmitting ultrasound signals into the subject and receiving reflected ultrasound signals therefrom. The reflected ultrasound signals received by the ultrasound probe are processed and a two-dimensional image of the target under examination is formed.
Unfortunately, this conventional equipment produces two-dimensional images even though the target under examination is three-dimensional. Also, the two-dimensional images represent a single thin plane taken at an arbitrary angle to the target making it very difficult to localize the image plane in the target and very difficult to reproduce an image at a particular location at a later time.
In U.S. application Ser. No. 08/419,049 and U.S. Pat. No. 5,454,371, assigned to the assignee of the present application, the contents of which are incorporated herein by reference, three-dimensional ultrasound imaging systems are described. Although, these systems overcome disadvantages associated with the prior art, improvements to enhance imaging and to increase the speed by which three-dimensional images can be generated from two-dimensional ultrasound images are continually being sought.
It is therefore an object of the present invention to provide a novel system and method for generating a three-dimensional image from a succession of two-dimensional images, and a novel ultrasound imaging system.